Strength and Conditioning Training Swindon Blog

Exercise Induced Muscle Damage: Implications for performance

Exercise induced muscle damage (EIMD) is the body’s response to changes in movement patterns leading to the regeneration of muscles and adaptation to performance ability.

Responses to EIMD have been categorised in to two areas; Primary and Secondary. Primary reactions to EIMD focus on the metabolic and mechanical changes. Metabolic responses have been suggested such as Hypoxia, which is the reduction of oxygen within the body and therefore the muscles (Ernsting, 1963. Robergs, Quintana, Parker, & Frankel, 1998). However, Farr (2006) demonstrated that EIMD was not alleviated through a treatment of hypoxia. The predominant amount of research on the primary response to EIMD focuses on the mechanical changes that occur from lengthening (eccentric), rather then isometric (static) and shortening (concentric), contractions (video 1) and causes damage to the muscle fibres (MF), which are long tubular structures that make up the length of the muscle, particularly alterations in the length of the individual sarcomeres, which are small structures that make up the length of the MF (Hunter & Faulkner, 1997. Jones, Newham & Torgan, 1989. McCully & Faulkner 1985. Proske & Morgan, 2001). The velocity (speed) of the movement will induce EIMD (Chapman, Newton, Sacco, & Nosaka, 2006) as will the work load of session (Lieber, Woodburn, & Friden, 1991) and the amount of force required during the bout (García-López et al., 2006).

Secondary responses to EIMD focus on the hours and days post exercise and have been demonstrated by Appell, Soares and Duarte (1992) and Yu, Carlsson and Thornell (2004) that alterations to the MF cause a chain reaction that leads to regeneration, which can occur as little as 2 weeks following (Clarkson & Tremblay, 1988. Mair et al., 1995). These responses are mostly seen in fast twitch muscle fibres (Chapman, Newton, Sacco, & Nosaka, 2006. Lieber, Woodburn, & Friden, 1991) although have been shown in slow twitch fibres recently (Mair et al., 1995) and is caused by either a novel, or first time, bout of exercise (Brown, Child, Day, & Donnelly, 1997) as well as endurance based performances (Mair et al., 1995).

Several strategies in countering the effect of EIMD have been studied including supplementation of Antioxidants such as Vitamin C and E, nutritional supplementation in the form of protein and carbohydrate intake, stretching, massage, cryotherapy and the Repeated Bout Effect (RBE). Vitamin C of 400-3000mg per day for between 4 and 14 days prior to exercise shows some positive effects from EIMD (Bryer & Goldfarb, 2006. Kaminski & Boal, 1992. Thompson et al., 2001). However, Vitamin C less then 3 days prior has no effect (Connolly, Lauzon, Agnew, Dunn, & Reed, 2006). Connolly, McHugh, & Padilla-Zakour (2006) showed positive responses to reducing muscle soreness and loss of force production when consuming 0.6 litres of unsweetened cherry juice 4 days prior and post exercise. This procedure is highly recommended as it is relatively easy to implement and follow for a team.

Although little research has been performed on nutritional supplementation to prevent EIMD, there is evidence that consuming a ration of 4:1 carbohydrate to protein blended drink before, during and after can attenuate the effects of EIMD from endurance exercise (Saunders, Kane, Todd, 2004) and carbohydrate only supplementation has no effect on reducing EIMD (Nelson, Conlee & Parcell. 2004) leading to a recommendation of a carbohydrate/protein blended drink being consumed before and after heavy training sessions such as fitness based field sessions.

A blend of stretching before exercise and massage after has shown positive effects on muscle force and Range of Movement (ROM) (Rodenburg, Steen been & Schjereck, 1994.) However, no improvements were seen in DOMS or flexibility. Pizza, Koh, Mcgregor and Brooks (2001) and Koh, Peterson, Pizza and Brooks (2002) show that passive stretching 2 weeks before exercise can protect the muscle cells by preparing the body to react in a protective manner. It is recommended that all participants who are not used to exercise are given a stretching program for 2 weeks or more before training commences. Once participants are established in a training program it is recommended to stretch for at least 10 minutes before exercise and receive 15 minutes of massage after.

The most effective preventive method has been shown in the Repeated Bout Effect (RBE) (Brown, Child, Day, & Donnelly, 1997. Marginson, Rowlands, Gleeson, & Eston, 2005). Hough (1902) was the first researcher to show that trained muscle incurred less EIMD then untrained. Clarkson and Tremblay (1988) showed that exercise, even in small bouts, will produce smaller extents of EIMD after the primary bout and each subsequent bout will result in faster repair of the muscle with the positive effects of RBE lasting 6 to 9 months (Nosaka, Sakamoto, Newton, & Sacco, 2001). Marginson, Rowlands, Gleeson and Easton (2005) studied RBE on adult and adolescent males and showed that the younger males responded even more to RBE by showing almost no symptoms of EIMD after their second bout of exercise due to the flexibility children have, naturally being more active and having fewer fast twitch muscle fibres that have been highly associated with EIMD. Further studies show exercise on damaged muscles will not increase the damage seen and will not decrease the rate of recovery, however it will impede muscular adaptation (Nosaka & Clarkson, 1995. Nosaka & Newton, 2002. Paddon-Jones, Muthalib, & Jenkins, 2000).

It is recommended that participants ensure they consume 0.6 litres of unsweetened cherry juice 4 days before and after exercise bouts, drink a 4:1 carbohydrate/protein drink 2 hours before and immediately after all training sessions, stretch for 2 weeks before beginning training if they are currently untrained or, if currently active, stretch before each exercise session and ensure they receive massage for 15 mins after intense sessions. The most important recommendation is for all team members to maintain a high level of exercise sessions per week to ensure the body continuously regenerates itself from exercise damage.

About SGFitnessTeam

International Powerlifter Charlie Shotton-Gale offers this unique service in to the world of health and fitness by introducing you to goal specific training, lifestyle complimenting nutrition and diet advice and positive support to enhance your lifestyle change.
As a Powerlifter, Charlie is 3 times British Champion, Commonwealth record holder and ranked in the top 10 in the world.